Is It Hot in Here? Build a Temperature Sensor
MOST CAR DASHBOARDS HAVE A TEMPERATURE gauge that shows the relative temperature of the engine. This readout warns you if the engine is getting too hot, because an overheated engine can mean that something might be wrong and you should stop the car. Most dashboards also have an indicator light that illuminates when the engine reaches a temperature that is too high; you probably won’t be able to see it on the dashboard because it is normally switched off. It might look something like Figure 9-1 when it’s on.
FIGURE 9-1 A typical temperature indicator on a dashboard
In this experiment, you’ll ...